Pearl Information Centre
The pearl is a gem that has held a magical place in human history for thousands of years. A pearl is made of layers of nacre secreted onto a foreign object, which a living mollusc can not expel from its body.
A Natural Pearl
...is formed as an accident of nature in a wild animal.
Pearls can be found in Oysters, Mussels, Conch Shell, Clams, and Abalone.
A Cultured Pearl
… is created through the intervention of man.
History of Natural Pearls
Coveted by Kings, Queens and Emperors, a natural pearls rarity ensured only the powerful and wealthy could afford them. Natural pearls in human history date back to 6000BC.
Anne of Denmark, Queen of England 1574 – 1619, wife of James I of England wearing elaborate pearl jewellery and gown covered with pearls.
Queen Marie of Bavaria. 1848 -1864
wearing large natural Freshwater pearls harvested from Bavarian streams
Decline
All these pearls from history are of course natural pearls and sadly most of these fisheries have been wiped out due to over fishing.
History of Cultured Pearls
500 BCAs early as 500 BC the Chinese freshwater mussel was used for culturing Mabe Pearls. A technique that has not changed for centuries. |
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1700’sCarl von Linne developed a pearl culturing technique that remained a secret for 144 years. |
1900’s
It was Tatsuhei Mise and Kokichi Mikimoto both of Japan, in around 1895 that perfected the technique of inserting a shell bead nucleus with a mantle tissue graft that proved commercially successful in producing loose pearls in oysters.
Akoya pearls made famous by Mikimoto and the beautiful women who wore them.
Cultured Saltwater Pearls
Akoya Oyster
Pinctada Fucata
Oyster 80 - 100mm. Pearls 2 - 10mm White, Cream, Grey.
Above a Chinese Akoya farm at work. Due to a decline in Japans water quality and disease, China has become the main producer of Akoya Pearls.
Known to have a “shiny” lustre and a good round to near round shape due to a thin coating of nacre.
Rainbow Lipped Pearls
Pteria Sterna
Oyster 60 - 140 mm. Pearls 6 - 11mm. Mabe 12-15mm. Blue, Rose, Grey.
Also known as New World Black Pearls producing a beautiful range of natural colours. The oyster lives in the eastern pacific from Baja California to Peru.
Cultured Saltwater Pearls
Silver / Golden Lipped Oyster
Pinctada Maxima
Oyster 200 - 300mm. Pearls 6 - 20mm White, Gold
Pinctada Maxima grow the most valuable pearls in the world. Their silky lustre, thick nacre, large size and natural white, silver white and rich gold colours make them exquisite, desirable and expensive.
Seeding
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An oyster from either a hatchery or collected from the wild, is “seeded” with a nucleus and a mantle tissue graft. An incision is made near the gonads of the animal where the graft and nucleus will be placed. The mantle tissue will proliferate and grow around the nucleus to form the “pearl sac” and secrete nacre onto the seed that over years |
The nucleus (seed) is made from the “Washboard” mussel shell found in the Mississippi River. The seeds cost
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Cultured Saltwater Pearls
A Pearl Farm
Producing a cultured South Sea Pearl takes up to 2 years, is labour
intensive, requires specialised boats and highly skilled technicians. Producers are often challenged by the many risks of an ocean environment.
An oyster is handled some 75 times before its first harvest
Often located in beautiful and remote places the farms are difficult and costly to run.
Keshi pearls
During harvest a secondary seedless pearl is sometimes found, instead of, or
in addition to, the seeded pearl. This pearl is called a “Keshi” Pearl. Being seedless it is usually small and baroque and is solid nacre.
Black Lipped Oyster
Pinctada Magaritifera
Oyster 150 - 250mm. Pearls 8 - 18mm Grey, Black
Cultured Saltwater Pearls
Paua Abalone
Haliotis iris
Abalone 160mm. Pearls - Mabé 7 - 21mm Violet, Blue, Green, Gold, Pink.
Paua Abalone at home on NZ pearl farm. They are fed sea weed regularly.
A pearl takes at least 18 months to grow
and only 30% of shell produce saleable pearls.
Mabé Pearls
Mabé Pearls are a half pearl grown dir ectly on the shell produced in both freshwater and saltwater species.
Cultured Freshwaterwater Pearls
Triangleshell Pearl Mussel
Hyriopsis cumingii
Mussel 80-100mm. Pearls 1 - 15mm White, Cream, Pink, Apricot, Lavender.
Various other species and hybrids are used in freshwater cultured pearling. Freshwater Pearls come in a wide variety of natural colours.
The mussels are suspended in nets during their grow out period.
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A mussel is seeded with on average 20 to 30 pieces of mantle tissue from a donor mussel, directly into the mantle tissue
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A mussel is seeded with on average 20 to 30 pieces of mantle tissue from a donor mussel, directly into the mantle tissue |
Mother of Pearl (MOP)
The humble button is what put Broome and its pearling on the map.
Pearl Treatments
Bleaching
Bleaching lightens and evens out colour, is permanent
and in most cases undetectable. It is a process that has been used for decades and is considered standard industry practise in Akoya and freshwater Pearls.
Pearl Enhancement
Most pearls are treated to simply enhance their natural beauty, a technique mastered by the Japanese called mishori. Japan still processes large quantities of pearls from around the globe. Understandably these processes are a closely guarded secret.
Dyed or Coloured Pearls
Fake Pearls
Shell based pearls are fake pearls
What defines a Gem
Beauty, Rarity and Durability.
This is the criteria applied to all gems. It stands to reason therefore that the bigger rounder and more perfect a pearl the more expensive it is as it is rare and beautiful.
Grading a pearl
Pearls are graded using 5 criteria.
Lustre, Surface, Shape, Size and Colour.
Remembering that every pearl is a product of nature
and therefore each one unique.
Lustre
Lustre is the reflection of light from the surface, which is the most important quality aspect of a pearl.
The shinier the pearl appears the better the lustre.
Pearls refract and reflect light. Pearls with higher refraction
allow you to almost look into the pearl where you can see the colours of the rainbow or iridescence. This is called the orient of the pearl which is
often considered the sixth criteria.
Surface
Surface is the other significant quality consideration.
No surface marks or imperfections are very rare.
A pearl with up to 3 small marks is still considered top quality. Any uneven surface will also diminish the value of the pearl.
Grading a Pearl
Shape
Some shapes are rarer and in higher demand than others. For instance the rounder a pearl gets, the rarer it is, the more expensive it gets and quite rapidly so. Nice tear drop shapes are also in demand
and only a small percentage of a harvest.
Size
As with all gems size matters, different species however are capable of different sizes.
A pearl is usually measured by the horizontal plain by which it is strung or worn
Colour
Rarity and fashion are the main criteria that will give value to colour. Your skin colour can be an important consideration when choosing a pearl.
This is a small representation of the natural colours possible
from molluscs of the world.
There is currently no universally recognized pearl grading system.